1. Field
The present invention relates to a head mounted display, and more particularly to a see-through-type head mounted display which projects image light corresponding to display information onto an eye of a user while allowing the transmission of an external light through the head mounted display.
2. Description of the Related Art
Conventionally, there has been known an information processing device which includes a memory unit for storing various display information such as moving image files, still image files and text files, and a playing unit for playing the display information stored in the memory unit.
A typical example of such an information processing device is a personal computer. In general, the personal computer is constituted of a computer body provided with the memory unit, the playing unit and the like, a mechanical manipulation unit such as a key board or a mouse which a user manipulates to allow the computer body to perform predetermined operations, a display which displays the display information reproduced by the playing unit as an image and the like.
As the display which displays the display information, a display device which is used in such a manner that the display device is placed on a table such as a CRT (Cathode Ray Tube) display or a liquid crystal display has been adopted in general. On the other hand, there has been also developed a head mounted display (also referred to as HMD) or the like which uses a liquid crystal display element as an image display device and allows a user to visually recognize an image while wearing the head mounted display on his head.
Further, recently, there has been also developed a head mounted display having the following constitution. That is, the head mounted display includes an optical scanning part which scans image light generated based on the image signals (hereinafter referred to as “image light”) in two dimensional directions and guides the scanned image light to an eye of a user, and displays the two-dimensionally scanned image light on a retina of the user by projection by operating the optical scanning part in a state where the user mounts the head mounted display on his/her head thus allowing the user to visually recognize an image.
As such an HMD, there has been known a see-through type HMD which allows a user to visually recognize an external field of view in a see-through manner. With respect to such a sea-through-type HMD, for example, JP-A-2003-242168 discloses an HMD in which infrared rays are irradiated to an identifying object such as a bill, and content information associated with the identifying object is displayed based on an identifying object ID or the like obtained by the reflection of the irradiated infrared rays in a state where the content information is superposed on the identifying object.